Vehicle-spring



s. A. THRELKELD.'

VEHICLE SPRI NG. APPLICATION FILED FEB, I3, 1920.

Patented Sept. 20,1921.

film: Help,

UNITED STATES,

PATENT OFFICE.

OF HUTCHINSON, KANSAS.

VEHICLE-SPRING.

Application filed February T all whom it may concern Be it known that I, STEPHEN ARTHUR THRELKELD, a citizen of the United States of America, and a resident ofH utcliinson,

county of Reno, and State of Kansas, have invented certain new and useful Improvements in Vehicle-Springs, of which the following is a full and clear specification.

This invention relates to springs of the bowed leaf type and its object is to provide a spring which shall be supplemental to the main bow spring in that it will be virtually out of action until one of the conditions arises which is designed to bring it into action. It is designed to be brought into action as a load spring whenthe load is in. creased beyond a certain degree, to thereb assist the main spring in carrying the loa and. in like manner it comes into action upon any sudden descent of the vehicle body, in which case it performs the function of a shock absorber; and another function of this supplemental spring is to absorb and break up excessive rebound action of the body, the arrangement being such that upon a very excessive rebound movement of the vehicle body the full strength of this supplemental spring is brought into action to supplement the resistance offered by the main spring after the same is bowed beyond normal curvature, therebygreatly assistin in preserving the main spring against reakage by excessive rebound strains, as more fully hereinafter set forth.

' In the drawing- Figure 1 is ,a rear elevation of a motor vehicle showing my spring applied thereto; Fig.- 2 is a side elevation showing the manner of applying the spring as a side- 40 spring Fig.'-3. isa side elevation of my spring detached from the vehicle.

Referring to Fig. 1 of the drawing, adesignates a bow sprin of the usual type, constructedof a plurality of superposed leaves connected rigidly together midway their length and to the body of the vehicle. The downwardly-curved ends of the main, longest, leaf of the spring are connected to 60 shacklesb of the usual. type, which pivotally depend from the inwardly-extending ends of brackets c fastened, by -means of their base-plates b,

I i to the top of the rear axle housing, the upper faces of these base-plates I) being flat and smooth and being directly Specification of Letters Patent. Pate t d S t 20 1921 s, 1920. Serial No. 358,385.

opposite (i. 6., below) the pivot supports of the shackles b, there being a clearance space between the lower end of each shackle and its adjacent base-plate b.

Aflixed rigidly to the under side of the aforesaid main spring is a supplemental spring d of the same type and of approximately the same length, the supplemental spring being curved to'correspond with and fit against the under side of the long leaf of the main spring. The lower (11. 6., longest) leaf of the supplemental spring curves downwardly to a point under the shackles b, their extreme ends being curved upwardly at d at a point directly under the ad acent eye of the main spring. Normally, that is, without a load or with alight load,

the curved ends d of the supplemental spring lie in the eyes of the main spring and the base-plates b"; without a load, that is, in normal condition, such as shown in Fig. 3, the curved ends cl may lie close to the end eyes of the main spring, as it is necessary simply that when unloaded or when carrying only a' light load the ends (1 shall be out ,of contact withthe base-plates b.

It will be observed that the supplemental spring when thus constructed and located will not come into action until a predetermined load is carried by the vehicle, and that when this increased load is carried the curved ends (1' of he supplemental spring will be brought into contact with the upper, rub, sur aces of the base-platesb and thus supplement the main sprin in supporting the load. In this way, ,get the advantage of carrying the vehicle on light,

resilient springs so long as the load is light enough to be safely carried thereby, but, when the load is increased to a point where resilience must be sacrificed to load-sustaining capacity, the supplemental spring is brought fully into. action to thereby practically double thesu'" orting capacity of the spring appliance. uring the usual vibrations of the vehicle, the ends d of the sup- KANSAS, .A SSIGNOR OF ONE-HALF.

spaces between the endplementalspring will slide back and forth on the rub-irons b, the curvature of said endsof the springs serving to facilitate this free sliding action. It will be observed that. the same action will occur upon any sudden descent of the'body far enough to bring the ends d into contact with the rubplates, in which case the supplemental spring one part of the vehicle and at will then act as a shock absorber. A further important function of the supplemental spring is to check excessive rebound of the vehicle, this being accomplished by the catching of the; curved ends 03 under the end eyes of the main spring upon any excessive upward rebound of the Vehicle body. When the vehicle body thus rebounds sufiiciently far to thus engage the curved ends d under the ends of the main spring, it will be seen that the full strength of all the leaves of the supplemental spring and in addition the lower, longer, leaf of the main spring will be brought into play to check the rebound, thereby practically eliminating danger of breakage of the main spring from rebound action.

In Fig. 2 my spring appliance is shown applied as a side spring inthe well-known manner. The operation of the spring when thus used will be obvious from the foregoing description of the function and operation as set forth in connection with the construction illustrated in Fig. 1.

The nature and scope of the invention havin been thus indicated and its preferred embo iment having been specifically described, what is claimed as new is:

1. A vehicle spring appliance comprising a main bow' spring, a supplemental bow spring curved to substantially correspond with the main spring and fitted against its inner side and rigidly secured to the main spring at the centers of the two springs, the two springs being of approximately the same length, the extremities of the inner, supplemental, spring being shaped to lie under the end eyes of the main spring and disconnected therefrom and be engaged with said end eyes when the main spring is deflected.

2. In combination with a vehicle, a main bow spring attached midway its length to its ends to the relatively movable othen part of the vehicle, a supplemental spring shaped to substantially correspond therewith and rigidly affixed at its inner concave side, this supplemental spring being approximately of the same length as the main spring and hav} ing curved ends adapted to engage under the ends of the main spring, rub-surfaces being provided on the part of the vehicle adjacent to said curved ends of the supplemental spring, whereby an excessive load on the vehicle will flex the mainspring far enough to bring said curved ends of the supplemental spring into sliding action with said rub-surface, for the purpose set forth.

3. A vehicle spring appliance consisting of two bow springs fitting one against the under side of the other and rigidly connected together midway their length, said two springs being of approximately the same lengt the outer spring being provided with a shackle-eye at e 'ch end and the inner spring being provided with a curved portion at each end engaging under the ,adacent eye of the main spring, when the main spring is deflected.

A vehicle spring appliance consisting of an outer bow spring having a shackle-eye at each end, an inner, supplemental, bow spring fitting against the concave side of said outer spring and of approximately the same length and rigidly attached thereto midway the length of the spring, the extremities of the inner spring being curved under the eyes of the main spring, a pair of brackets having one end pivotally shackled to one of the eyes of the main spring and each being provided with a rub-surface lying at a point opposite the adjacent eye of the main spring and in close roximity to the adjacent curved end of t e supplemental spring, whereby under the conditions set forth the supplemental spring will have the function either of a loadpring or a shockabsorber or a rebound-check.

5. In combination with a vehicle, spring composed of a plurality of leaves fitted together, a supplemental spring attached to the concave side of said main spring and composed of a plurality of leaves fitted together, these leaves being progressively of increasing length, the shorter one lying against the concave side of the main spring, the extremities of the long leaf of the supplemental spring curving under the ends of the .longleaf of the main spring and being unattached thereto and being engaged withsaid end eyes when the main spring is deflected.

In testimony whereof I hereunto afiix my signature.

STEPHEN ARTHUR "I'HRELKELD. 

